This invention relates to a composite casting process for manufacturing components which comprise castings of silicon-containing aluminum alloys and are intended to define the combustion chamber of internal combustion engines, and shaped elements, which are bonded to the castings at surfaces to be subjected to high thermal and/or mechanical loads and consist of inorganic non-woven fibers or whiskers and have a fiber or whisker volume of 10 to 50% and have been infiltrated with an aluminum alloy which has a melting point that is higher, preferably by 30.degree. to 140.degree. C., than the melting point of the aluminum alloy of the casting, which infiltration is effected under a pressure which is maintained until said infiltrating aluminum alloy has solidified and in such a manner that the infiltrating aluminum alloy forms on the shaped element a cover layer in the regions in which the shaped elements are to be bonded to the casting.
In a composite casting process for manufacturing fiber-reinforced components of internal combustion engines, such as pistons and cylinders, the infiltrating metal is permitted to solidify under an elevated pressure so that a fiber-reinforced shaped element is obtained in a first process step and that shaped element is then placed in a predetermined position into the mold for making the casting and is bonded to the casting by a low-pressure casting process in which molten material is used which is at a temperature above the melting point of the cover layer and below the melting point of the core region of the shaped element (German Patent Specification No. 27 01 421).
A disadvantage of that composite casting process resides in that the casting of the aluminum alloy in contact with the shaped element which comprises a cover layer consisting of an aluminum alloy is rendered very difficult by the presence of oxides on the cover layer so that the formation of a bond between the cover layer and the aluminum layer of the casting throughout their interface is adversely affected or may be inhibited in numerous cases.